The intent of the macro was to force information into cell(s) once, but allow
the user to change the information if they had better numbers.

The macro - works correctly the first time - but it overrides any changes
entered by the user.

Sub Worksheet_Change(ByVal Target As Range)
Dim lookrng1 As Range
Dim lookrng2 As Range
Dim lookrng3 As Range
Dim lookrng4 As Range
Dim lookrng5 As Range
Dim key2 As String
Dim SW As String
Application.EnableEvents = True

If Left(Range("Prod1").Value, 3) = "LBD" Then
SW = "off"
ElseIf Left(Range("Prod1").Value, 3) < "LBD" And SW < "used" Then
SW = "on"
End If

If SW = "on" Then
Range("d17").Value = Range("c9").Value
Range("d19").Value = Range("c9").Value
SW = "used"
End If